1. Field of the Invention
The present invention relates to a wheel hub, and more particularly to a wheel hub having a hydraulic driving mechanism for driving wheels of cycles or vehicles.
2. Description of the Prior Art
Typical wheel hubs comprise a wheel axle attached or secured to cycles or vehicles, and a hub shell rotatably attached onto the wheel axle, and secured to wheels of the cycles or vehicles, for rotatably coupling or attaching the wheels to the cycles or vehicles with the wheel axle.
For example, U.S. Pat. No. 4,738,551 to Chi, and U.S. Pat. No. 5,024,121 to Hsieh disclose two of the typical wheel hubs each also comprising a hub shell rotatably attached onto a wheel axle which is attached or secured to the cycles or vehicles, for rotatably coupling or attaching the wheels to the cycles or vehicles with the wheel axle.
However, the typical wheel hubs do not include any driving devices or mechanisms to drive or to rotate the wheels and the hub shells relative to the wheel axles. Normally, the typical wheel hubs include a unidirectional driving device or mechanism disposed therein to control the wheel to rotate relative to the cycle or vehicle in one direction only.
Typical motor cycles, vehicles, trains, trucks, etc. are rotated or driven by motors or engines. Recently, a hydraulic engine has been developed and attached to the motor cycles, the vehicles, the trains, the trucks, or the like, for driving the vehicles, instead of typical motors or engines. One example of the hydraulic engines has been disclosed in U.S. Pat. No. 6,736,099 to Mori et al.
However, the typical vehicles may not be driven without the typical motors or engines and the hydraulic engines, and both the typical motors or engines and the hydraulic engines may occupy a great volume of the vehicles.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional wheel hubs for cycles or vehicles.